Gelatinized explosive.



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nxm: AUBEBT, 03F ENGENE, SAETRE, NORWAY, AND SIGU'BD ADOLF GUSTAF SSON NA'UCKHQFF, OE VINTERVIKEN, LIIJEHOLMEN, SWEDEN.

GELA'IINIZED EXPLOSIVE.

To all whom it may concern:

' Be it known thatwe, AxnL Aunnn'r, engineer, subject of the King of Norway, residing in Eugene, Saetre in the Kingdom of Norway, and sworn doom Gusrxrsson Nanoxnorr, engineer, subject of the King of Sweden, residing in Vmterviken, Llljeholmen, in the Kingdom of Sweden, have invented certain new and useful Improvements in Gelatinized Explosives, as set forth in the annexed specification. It has hitherto been known that the rapidity of detonation of an explosive depends on its density or gravimetric weight. This fact especially appears in the use of pulverous explosives and explosives compressed to solid consistency. The rapidity of detonation is increased with increased density to a certain limit, whereupon it rapidly decreases until it at last at a high compression sinks to zero, that is to say, the explosive finally loses its power to transmit the detonation. The plastic explosives show in some degree in this respect the same property.

By a long series of experiments we have found, that the amount of air contained in an explosive, whether the air is dissolved in the explosive or included in the explosive 1n the form of air-bubbles has a great influence on the rapidity of detonation of the explosive. This fact in some degree relates to the above mentioned circumstance-. e. the dependence of the rapidity of detonation of the explosive on its densitybut it has appeared, that thevariations in the amount or ercentage of air, contained in the explosive, y themselves are of a very great importance for the variations of the rapidities of detonation. This fact appears especially clear in the plastic explosive. In usual blasting elatin (containing 93% nitroglycerin and g 0 nitrocellulose) the rapidity of detonation can in consequence of the variations in the percentage of air contained therein vary from less than 1000 meters per second to over 7000 meters per second.- We have found that through evacuating blasting gelatin its rapidity of detonation can be reduced and that on the contrary through the admixin of air into the blasting gelatin a high rapldity of detonation can be obtained. This is also the case with gelatin-dynamites Specification of Letters Patent.

npplicatioufiled January 25, 1915,. Serial No. 4,225.

. ciently great Patented nine 6, 19116.

and other plastic explosives. The extremely of detonation of these substances being found in the literature are explained through the fact that regard has not been taken to thepercentage of air contained in the explosives in question. Hereby is also the fact explained, that explosives of for the rest analogous or equal composition, but manufactured in difierent ways, show unequal rapidities of detonation. The known fact, that most explosives through storing get a lower briskness, is also hereby explained. Fresh blasting gelatin, which still contains the numerous air-bubbles, admixed or worked in through the kneading, detonates, as we often have found, with a rapidity of 7000 meters per second but after some time, the air having escaped, its rapidity of detonation is lowered to for instance 2000 meters per second.-

The mere knowledge about the influence of the amount of air, contained in the explosive on the rapidity of detonation is so far without practical importance, as the air which is contained in the explosive in the form of bubbles, has a tendency to escape during the storing, whereby the rapidity of detonation is lowered. We have now found that for the manufacture of an explosive, which shall durably keep its contents or percentage of air such porous substances must be added, which do not lose their contents of air. As additional components in explosives are already a number of substances used, which in some degree act in the above described manner, as

.for instance wood-meal, meal, starch and the like. However, in order to have a suffiuantity of air incorporated into the exploslve, with the use of said substances, generally too large quantities thereof must be used, which, for other reasons, is not suitable, besides which, it has appeared, that the additions of the kind above mentioned, hitherto used, have not the capacity durably to keep the air.

The present invention has for its object, by the use of the least possible quantity of additional substances, to incorporate airbubbles in the explosives in such a way, that the quantity of air incorporated is durably retained therein, whereby the rapidity of detonation and briskness of the explosive remain constant during a long time. We have found, that cork, in the form of small corns or powder is especially well suited for said purpose.

Experiments made by us have shown that through addition of cork powder to, for instance, blasting gelatin or gelatin-dynamite, explosives of an extremely high briskness may be produced. This increase of the briskness can be verified as well by tests with the aid of the so-called Trauzls lead-block (see for instance fKast: Anleit'zmg zm' Ohemz'scken and Physikalischen Untersuchung dew Sgzweng- 'u/nd Zz'indstofie,? page 1027) as especially by the so called crushing test. (See, for instance, the cited work by Kast, page 1030).

With the expression cork there is in this patent meant cork-substance in the widest sense of the word, as for instance cork from Quercus suber, Quercus occidentalz's, Quercus ilew and Quercus pseudosuber or other plants. It is however of importance that the cork powder be not ground too fine, so that the airfilled cells be spoiled. z

The cork powder can be added in natural, dried, or slightly carbonized condition. As

above stated the present invention is not limited to any especial composition of the explosives. As examples of compositions I of different types of explosives to which the present invention is applied the following may be stated:

Example 1: 9099.5% blasting gelatin (nitroglycerin and nitro-cellulose). 0.510% cork-powder or the like materials.

Example 2: 5070% gelatinized nitroglycerin. 20-40% potassium-, sodiumor ammoniumnitrate or. mixtures thereof. 110% corkpowder or the like materials.

Example 3: 56% nitroglycerin. 2.3% nitrocellulose. 1.7% nitrobenzene.

'ammoniumnitrate. 5% corkpowder or the like materials.

Example 4: 65% nitroglycerin. 1.7% nitrocellulose. 28% sodiumnitrate. 5.3% corkpowder or the like material.

Example 5: 50-60% potassiumor sodium chlorate or perchlorate. 25-35% nitrohydrocarbons (with or without nitroglycerin) gelatinized with nitrocellulose. 110% corkpowder or the like materials.

Example 6: 50% ammonium perchlorate. 20-30% sodium nitrate. 25-35% nitrohydrocarbons (with or without nitroglycerin) gelatinized with nitrocellulose. 110% corkpowder or the like material.

Having thus described our invention, we declare that what we claim is:

1. Gelatinized explosive containing cork powder embedded in a matrix of a gelatinized detonating explosive comprising a normally liquid nitrated organic compound mixed with suflicient nitro-cellulose to efi'ect its gelatinization.

2. Gelatinized explosive of the class described containing blasting gelatin and cork powder.

3. Gelatinized explosive of the class described containing gelatinized nitroglycerin, cork powder and oxygen yielding salts.

4. Gelatinized explosive of the class described containing gelatinized nitroglycerin, cork powder and alkali nitrates.

In witness whereof we have hereunto set our hands in presence of two witnesses.

AXEL AUBERT. SIGURD ADOLF GUSTAFSSON NAUGKHOFF.

Witnesses to the signature of Mr. Axel Aubert:

T. T. HALLING,

BJAME L. SIMONSEN.

Witnesses to the signature of Mr. Sigurd Adolf Gustafsson Nauckhofi' AUG. HAGELIN, ALMA PETTERSSEN. 

